℃maj9 (pronounced C Major Ninth) is the 9th studio album by ℃-ute. It was released on December 23, 2015 in 3 editions: 1 regular and 2 limited editions. Limited Edition A includes the group's May 29th live at the LIQUIDROOM ebisu in Tokyo, from their ℃-ute Naruchika 2015 Tour, on DVD. Limited Edition B includes a collection of the group's MVs on Blu-ray Disc.

"Jounetsu Ecstasy" by Nakamura Yoshiki was one of the demo songs for the music-ru TV contest that KOUGA (the composer of "Gamusha LIFE") won. The YouTube video of the song has been set to private since the album information was released.

The instrumental of "Urayanjau" is used in the introduction and the instrumental of "Digitalic→0 (LOVE)" is used in the opening of Hello! Project Station as of January 27, 2016 (Episode #153).